1. Field of the Invention
The field of the invention disclosed and claimed herein is believed to be best exemplified by art which may be found in the United States Patent Office in Class 285, Subclasses 253, 382, 382.1, 382.2, and 420 in which a priliminiary search has been conducted.
2. Description of the Prior Art
The prior listed below was developed in an endeavor to ascertain patentable merit in the present invention, U.S. Pat. Nos.
166,735--WALWORTH PA1 911,250--MAGGIO PA1 1,765,221--FALLA PA1 2,166,524--GOODALL PA1 2,963,305--MILLER PA1 3,107,931--KILLIAN PA1 3,249,371--PETERMAN PA1 3,432,190--KUNZ PA1 3,572,778--CASSEL PA1 3,900,933--ENGMAN et al PA1 4,056,273--CASSEL
Of the art listed above, Miller is of interest in that it shows a lap joint relationship between pipes 13 and 14 with clamping ring 5 around both pipes 13 and 14 over lapped portions thereof, clamping ring 6 around an unlapped portion of pipe 14 adjacent the end of pipe 13, and member (19, 20, 21) interconnecting rings 5 and 6. The interconnecting member (19, 20, 21) being elongate and of relatively small in diametric dimension is highly suspect of low rigidity.
The Maggio and Cassel ('778) patents are of interest in that they show the use of U bolts in combination with cross bars to clamp the lap portions of pipe sections. In Maggio spacer member g is a thin sheet of metal or leather.
The Walworth patent is of interest in that a pipe coupling member B includes serrations on the inner surface thereof to grip the pipe sections A, A'.
The Falla patent is of interest in that it also discloses pipe couplings in which the clamps are interconnected, the interconnecting member 13 having little circumferential dimension appears to provide only minimal rigidity.
The Goodall, Killian, Kunz, Peterman, Engman et al and Cassel ('273) are of general interest only.